We have investigated this issue - analysis shows the following patch was
backported upstream to the 4.9 stable branch
(https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.235), and
subsequently to the Debian oldstable kernel
(https://tracker.debian.org/news/1187816/accepted-linux-49240-1-source-into-oldstable-oldstable/):
commit 269044c2199bf6b41e76a0bad86d167f0e03fa62
Author: Thomas Gleixner <[email protected]>
Date: Tue Aug 25 17:22:58 2020 +0200
XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt
XEN data pointer which contains XEN specific information.
However this patch has an issue (https://lkml.org/lkml/2020/9/30/352) - it was
fixed by the below patch, but this has not been backported (either in to the
4.9 stable upstream, or the Debian oldstable kernel):
commit 0891fb39ba67bd7ae023ea0d367297ffff010781
Author: Juergen Gross <[email protected]>
Date: Wed Sep 30 11:16:14 2020 +0200
xen/events: don't use chip_data for legacy IRQs
The solution is therefore to also backport the above patch to resolve the
problem (we will also be reporting this to Linux so the stable branches can
have it backported also).
Kind Regards,
Alex Brett
